Acoustical facing material for interiors



- Dec. 25, 1922. 1,449,073

R, GUASTAVINO4 AcousTcAl. FAclNs MATERIAL PoR INTERIORS.

Fuso JULY 8, 1922 2 SHEETS-SHEET l liv @jf-,1952, 604.5 Tf1 w/vo 2 SHEETS-SHEET 2 Een. 26, 1922.

R. GUASTAVINO. AcousTlcAL FAclNG MATERlAL FOR INTERIoRs.

FlLEo JULY 8. i922.

Patented Der. 26 i922..

'rre

RAFAEL,GUASTAVINO, 0F BAY SHORE, NEW YORK, ASSIGNOR T0 RaGU'ASTAVINO COMPANY, A CORPORATION 0F MASSACHUSETTS.

ACOUSTICAL FACING- MATERIAL FOR INTERIORS.

Application led July 8, 1922. Serial No. 573,646.

To all fio/wm t may concern:

Be it known that I, RAFAEL GUAs'rAvINo, a citizen of the United States, residing at Bay Shore, in the county of Suffolk and State of New York, have invented certain new and useful Improvements in Acoustical Facing Materials for Interiors, of which the following is a speciiication.

This invention relates to the art of acoustics, and more particularly to the novel utilization of a natural material whereby its inherent physical characteristics may be utilized for acoustical purposes, especially for facing walls and ceilings in auditoriums and the like to correct certain types of acoustical diiiiculties by the prevention of excessive reverberation and echo and injurious focusing of sound.

Primarily, it is the obj ect of the invention to render available for use, as an acoustical facing, structural natural stone of a porous characteristic, having interconimunicating` pores or air passages throughout its body, and which, according to the present invention, may be caused to extend to and open at the exposed cut surface. An example of stone of that character are certain stones of a lime formation which originally contained fossilized materials which in due process of time and nature have mostly been dissolved with the result of leaving a stratified structure havin air spaces and communicating channels. leretofore, such stone has been quarried and prepared in a promiscuous manner Without reference to any features of the present invention which'. renders the .same available for auditoriums and other places where it is necessary to employ a facing for the walls and ceilings possesslng maximum acoustical properties, and at the same time presenting pleasing decorative eifects.

When stone of the character-described is cut or laid, according to the requirements of the present invention, it possesses the property of absorbing sound waves to such a high degree as to be exceedingly valuable as a building material for the interior of buildings, particularly for auditorium's and other places where a maximum acoustical result is to be desired. In factaccording to the present invention, when stone of the particular character described is' cut across the grain or strata or when selected from pieces presenting such a section, and laid either in the form of a block or slab as the facing for a wall or a ceiling, the same may be made available to absorb in excess of iifteen per centum of sounds lying in the pitch between the middle C and the third octave above middle C, which are the characteristic sounds which distinguish articulate speech.

iVith these and other objects in view which will more readily appear as .the nature of the invention is defined, the same consists in the novel features and combination 'of features hereinafter more fully described, il` lustrated and claimed.

To illustrate, by way of example, the features upon which the present inveniton'is based, in the accompanying drawings,

Figure l is a graphic microscopic enlargment of a natural stone so cut as to provide the construction required by the present in* lvention.

Figure 2 is'a similar view showing how the patentedacoustical material (referred to herein) combines with the natural stone as a facing or backing therefor.

Figures 3, 4, 5 and 6 are sectional detail views, enlarged for the sake of clearness showing various ways of using the acoustical material as an interior facing.

Figure 7 is a face' view of a portion of a wall constructed in accordance with the present invention.

Figure 8 is a detail sectional viewillustrating the feature of fastening the stone slabs or blocks to the supporting wall with an anchor.

Figure 9 is a detail view4 illustrating the use of the invention in connection with a supporting wall surface made of wire lath` and metal.

Like references designate corresponding parts in the several figures of the drawings.

In carrying forward the invention there is selected a natural porous stone which, as hereinbefore stated, may be a stone of lime formation, which originally contained fossilized materials, which in due process of time and nature has mostly dissolved leaving innumerable numbers of spaces or pores in the body of the stone, which, may be made by the present invention to open through the exposed face of the stone so that the latter will possess the property of absorbing sound waves to such a high degree as to be exceedingly valuable as a material for facing interiors. Also, the kind of stone tical material, the filling material of course\ referred to, or its equivalent, will have sufficient hardness to stand ordinary loads, at the same time presenting a very pleasing appearance when properly tooled or processed, and also susceptible of pleasing ornamentation.

In Figure 1 of the drawings, asection of the said natural stone is shown, designated by the letter A, and indicated by the num eral 1 is the general trend or line of the stratification or layers of the materials which usually make up the body ofa porous stone of the kind referred to. lt is preferable in preparing this stone for use to cut through the sameat an angle to the stratifi cation to thereby form the outeror exposed face of the block or slab with the pores opening through such face. YWhen the stone is so cut, it may be utilized in the manner contemplated by the present invention.

Therefore, it will be apparent that by cutting the porous. stone at right angles, or at an angle generally to the line of stratification, the intercommunicating pores will open i through the exposed face S, which will be the face exposed to receive andv absorb the sound waves generated in the auditorium or room. Hence, it is proposed to incorporate the blocks or slabs of stone, cut as described',

in the wall or ceiling in such a manner that the face S will be exposed to the sound Waves, while the top, bottom and ends of the block or slab will be cemented or mortared as at to the adjacent blocks or slabs as shown in Figure 7.

In cases where the porosity of any particular stone is too large to absorb the audible sound Waves it may be necessary to close the pores, but that can only be done by using for that purpose sound absorbing material of the character described in a former patent of myself and W. C. Sabine, No. 1197956, dated September 12, 1916 (re-issued under No. 14.992). When such material is used for the filling of large pores in the cut stone, the effect will be to partly close up the large spaces on the Jface or back, or both face and back, of the stone so as to reduce the porosity to the required dimensions. The method of doing this may be varied: for instance, the stone after sawing and tooling could be laid horizontally on a table and the acoustical material referred to mixed and then spread over the stone in such a manner as to ll up all of the large pores, or the stone after setting may be troweled with the said acousto be made flush with the normal surface of the stone.

The combination of the natural stone with the filling of the acoustical material will give a composite material possessing a high degreeof sound absorption, that is, capable of absorbing sound waves between C1 and C7,

Leaders and the third octave above. Furthermore, the acoustical filling material may be made of the same color as the stone or of anentirely different color, thus giving a very desirable range of selection for pleasing color edects.

llt should be further observed that the porosity of some of the individual stones, or a large number of them, which may be selected for the purpose of the present invention, may be sueh\that it would be advantageous not only to close part of the large pores on the surface, by the acoustical filling material above referred to, but also to back the stones or slabs with a thick layer of the said patented acoustical material when the stone is set in the walls. A method of using the stone in that way would be to first cover the stone with a moderately heavy layer of the patented acoustical material on the back, and allow the same to set. This material will adhere very firmly to the stone `on account of its porosity or cavities and become an inseparable part thereof. The stone slabs or blocks so formed are then set on edge in the wall in mortar, and fastened to the supporting wall with anchors y in the customary method of setting marble slabs, as shown in Figure 8, or it may be backed up solid With a grout of cement or mortar as shown in Figure 9.

@ther methods of using the stone slabs i absorbed, but as the sound waves pass from the large pores of the stone into the small pores of the patented acoustical material, which forms the backing, they will be absorbed to a very large extent, somewhat in jthe manner provided for by the material of graded porosity referred to in the patent aforesaid. However, in the present invention I propose to use theJ natural stone with the larger pores for the front facing and the artificial product for the back, thus serving in a dual capacity as a backing and as a binding material between the stone and the` supporting wall surface. rlhe supporting wall surface may be of any usual masonry construction of stone wall, brick wall, concrete, or wire lath and metal. This modification is shown in Figure 9 of the drawings and in that figure of the drawings it will be and. particularly between the range of C3 observed that the reference letter g desig- 130 nates a metal frame to which is attached the wire lath or expanded metal h, and the letter i indicates a grout of cement or mortar applied to the wire lath or metal and upon which is laid the acoustical facing consisting of the stone l and the sound absorbing material B previously referred to.

The several detail figures of the drawings illustrate various combinations in which the natural stone material may be employed, some combinations involving air spaces and others not, but in all cases the special advantages and objects accomplished by the present invention are conserved, and it will be understood that various other combinations may be employed Without departing from the spirit or sacrificing any of the advantages of the invention.

In the examples shown in Figures 2 to 6 inclusive, A designates the natural acoustical stone, in block or slab form, B the aforesaid patented acoustical material, C mortar or cement, D air space, E any fibrous or granular material, and F the Wall or base.

I claim:

1. An acoustical construction for auditoriums and the like consisting of a facing of porous natural stone having intercommunieating pores opening through the exposed face thereof.

2. An acoustical facing for auditoriums and the like consisting of natural porous stone having its pores opening through its exposed face.

3. An acoustical facing for auditoriums I and the like consisting of natural stone with substantially parallel stratification and having its exposed face cut at an angle to the stratification presenting open 1ntercommuni'cating pores for absorbing sound.

4. An acoustical material for auditoriums tion, and a soundabsorbing coating appliedy to a face of the stone.

7. An acoustical construction consisting of a plurality of acoustical units of natural porous stone laid side by side and presenting open exposed faces, a supporting surface, and av sound absorbing filling between said supporting surface and the natural stone.

8. An acoustical construction consisting of a plurality of acoustical units of natural porous stone having a face cut at an angle to stratification, a supporting Wall surface, and a filling of sound absorbing material disposed between said supporting Wall sur face and said units.

9. An acoustical construction including a plurality of acoustical units of natural stone having intercommunicating pores, said units being laid in a position whereby the pores extend from front to back thereof. a supporting structure, and a body of sound absorbing material between said units and the supporting structure.

In testimony whereof I hereunto aiix my signature in the presence of two Witnesses.

RAFAEL GUASTAVINO.

Witnesses:

EMORY L. GROFF, VIRGINIA L. WATSON. 

